const promisel = new Promise((resolve, reject) => {
    console.log('promisel');
    resolve('success')
})

const promise2 = promisel.then(res => {
    console.log(res); // 去到微任务
})

// .then返回的是promise对象

console.log('1', promise1);
console.log('2',promise2);


// Promise1
// '1' Promise{<resolved> : 'resolve1}
// '2' Promise{<pending>}
// resolve1